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HERA-Team / hera_pspec

HERA power spectrum estimation code and data formats
http://hera-pspec.readthedocs.io/en/latest/
BSD 3-Clause "New" or "Revised" License
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Covariance averaging in uvpspec is only correct for thermal noise #231

Open aewallwi opened 4 years ago

aewallwi commented 4 years ago

The covariance averaging in uvpspec currently assumes that samples are uncorrelated in time, baseline, frequency, etc... This is true for thermal noise but will be incorrect for data that is cosmic-variance limited (such as inside of the wedge and measurements of the 21cm signal).

philbull commented 3 years ago

@JianrongTan @acliu Has this been solved by your recent changes?

JianrongTan commented 3 years ago

I think we don't. We haven't modeled the potential covariance matrix between different time instants and baseline-pairs, while we only tentatively compute the covariance matrix between different delay modes per time and baseline-pair.

acliu commented 3 years ago

That's right. @adeliegorce will probably be able to work on this a little bit at some point.